.page-about {
  --about-rail: 180px;
  --about-gap: clamp(24px, 4vw, 64px);
  --about-pad: clamp(48px, 7vw, 104px);
  --about-line: 1px solid var(--hair);
  --about-line-soft: 1px solid var(--hair-soft);
}

.page-about h1,
.page-about h2,
.page-about h3 {
  font-family: var(--font-display);
  font-weight: 900;
  letter-spacing: -0.03em;
  color: var(--ink);
}

.page-about h2 {
  font-size: clamp(26px, 3.4vw, 44px);
  line-height: 1.16;
  margin: 14px 0 0;
}

/* ---------- 首屏 ---------- */
.page-about .intro {
  padding: clamp(24px, 3.5vw, 48px) 0 clamp(40px, 6vw, 80px);
}

.page-about .intro__top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

.page-about .intro__jump {
  flex: 0 0 auto;
}

.page-about .intro__title {
  margin: clamp(20px, 3vw, 36px) 0 0;
  font-size: clamp(30px, 5.2vw, 68px);
  line-height: 1.08;
  max-width: 17em;
}

.page-about .intro__grid {
  display: grid;
  gap: clamp(24px, 3vw, 48px);
  margin-top: clamp(24px, 3vw, 40px);
}

.page-about .intro__lede {
  margin: 0;
  font-size: clamp(16px, 1.5vw, 19px);
  line-height: 1.85;
  color: var(--slate);
  max-width: 36em;
}

.page-about .colophon {
  margin: 0;
  border-top: var(--about-line);
}

.page-about .colophon__row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  padding: 10px 0;
  border-bottom: var(--about-line-soft);
}

.page-about .colophon dt {
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--slate);
}

.page-about .colophon dd {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--ink);
}

@media (min-width: 900px) {
  .page-about .intro__grid {
    grid-template-columns: minmax(0, 1.35fr) minmax(260px, 0.65fr);
    align-items: start;
  }
}

/* ---------- 时间轴 ---------- */
.page-about .timeline {
  display: grid;
  gap: clamp(20px, 3vw, 40px);
  padding-bottom: clamp(40px, 6vw, 88px);
}

.page-about .tl-rail {
  display: flex;
  gap: 6px;
  overflow-x: auto;
  padding: 0 0 10px;
  border-bottom: var(--about-line);
  scrollbar-width: thin;
}

.page-about .tl-rail__link {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--slate);
  text-decoration: none;
  padding: 8px 12px;
  border: 1px solid transparent;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .tl-rail__link:hover,
.page-about .tl-rail__link:focus-visible {
  color: var(--ink);
  border-color: var(--hair);
}

.page-about .tl-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: clamp(56px, 9vw, 132px);
}

.page-about .tl-item {
  position: relative;
  padding-left: clamp(16px, 2vw, 28px);
  border-left: 1px solid var(--hair);
  scroll-margin-top: calc(var(--header-h) + 28px);
}

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: -5px;
  top: 16px;
  width: 9px;
  height: 9px;
  background: var(--paper);
  border: 2px solid var(--cyan);
  transform: rotate(45deg);
}

.page-about .tl-item:target::before {
  background: var(--cyan);
  box-shadow: 0 0 0 4px rgba(23, 224, 200, 0.18);
}

.page-about .tl-item__year {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(40px, 6.5vw, 64px);
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--ink);
}

.page-about .tl-item__label {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 10px 0 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--slate);
}

.page-about .tl-item__label::after {
  content: "";
  height: 1px;
  width: min(120px, 22%);
  background: var(--hair);
}

.page-about .tl-item__title {
  margin: 14px 0 0;
  font-size: clamp(22px, 2.6vw, 34px);
  line-height: 1.24;
  max-width: 20em;
}

.page-about .tl-item__body {
  margin: 14px 0 0;
  font-size: 16px;
  line-height: 1.9;
  color: var(--slate);
  max-width: 38em;
}

.page-about .tl-media {
  margin: clamp(20px, 3vw, 32px) 0 0;
  max-width: 720px;
}

/* ---------- 深色带通用 ---------- */
.page-about .band {
  position: relative;
  overflow: hidden;
  padding: var(--about-pad) 0;
}

.page-about .band--ink {
  background: var(--ink);
  color: var(--paper);
}

.page-about .band--ink::before {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: min(460px, 62vw);
  height: 100%;
  background: linear-gradient(160deg, rgba(122, 92, 255, 0.3), transparent 64%);
  pointer-events: none;
}

.page-about .band--panel {
  background: var(--ink-soft);
  color: var(--paper);
}

.page-about .band--panel::before {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: min(420px, 58vw);
  height: 62%;
  background: linear-gradient(20deg, rgba(23, 224, 200, 0.12), transparent 70%);
  pointer-events: none;
}

.page-about .band__inner {
  position: relative;
  z-index: 1;
  max-width: 1480px;
  margin: 0 auto;
  padding: 0 clamp(16px, 4vw, 48px);
}

.page-about .band h2 {
  color: var(--paper);
}

.page-about .band p {
  color: rgba(244, 240, 230, 0.78);
  line-height: 1.85;
}

.page-about .band .media-frame__caption {
  color: rgba(244, 240, 230, 0.62);
}

/* ---------- 三个小组 ---------- */
.page-about .team__lede {
  margin: 16px 0 0;
  max-width: 42em;
  font-size: 16px;
}

.page-about .team__grid {
  display: grid;
  gap: clamp(22px, 3vw, 34px);
  margin-top: clamp(28px, 4vw, 52px);
}

.page-about .role {
  padding-top: 16px;
  border-top: 2px solid rgba(23, 224, 200, 0.48);
}

.page-about .role__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--cyan-soft);
}

.page-about .role h3 {
  margin: 10px 0 0;
  font-size: clamp(20px, 2vw, 26px);
  color: var(--paper);
}

.page-about .role p {
  margin: 10px 0 0;
  font-size: 15px;
}

.page-about .role__daily {
  margin-top: 14px !important;
  padding-top: 12px;
  border-top: 1px solid rgba(169, 198, 201, 0.24);
  font-family: var(--font-mono);
  font-size: 12px !important;
  letter-spacing: 0.06em;
  color: var(--cyan-soft) !important;
  line-height: 1.7 !important;
}

.page-about .team__media {
  margin: clamp(28px, 4vw, 52px) 0 0;
  max-width: 880px;
}

@media (min-width: 760px) {
  .page-about .team__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 1080px) {
  .page-about .team__grid {
    grid-template-columns: 1.1fr 0.9fr 1fr;
    align-items: start;
  }
  .page-about .role:nth-child(2) {
    margin-top: clamp(0px, 3vw, 44px);
  }
  .page-about .role:nth-child(3) {
    margin-top: clamp(0px, 1.4vw, 20px);
  }
}

/* ---------- 更新节奏 ---------- */
.page-about .cadence {
  padding: var(--about-pad) 0;
}

.page-about .cadence__lede {
  margin: 16px 0 0;
  max-width: 42em;
  font-size: 16px;
  line-height: 1.85;
  color: var(--slate);
}

.page-about .cadence__list {
  list-style: none;
  margin: clamp(24px, 3vw, 40px) 0 0;
  padding: 0;
  border-top: var(--about-line);
}

.page-about .cadence__row {
  display: grid;
  gap: 8px 24px;
  padding: clamp(18px, 2.4vw, 28px) 0;
  border-bottom: var(--about-line);
}

.page-about .cadence__k {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.14em;
  color: var(--ink);
}

.page-about .cadence__v {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--slate);
}

.page-about .cadence__tag {
  margin: 0;
  justify-self: start;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--orange-deep);
  border: 1px solid rgba(184, 56, 10, 0.35);
  padding: 4px 8px;
}

@media (min-width: 820px) {
  .page-about .cadence__row {
    grid-template-columns: 190px minmax(0, 1fr) 110px;
    align-items: baseline;
  }
  .page-about .cadence__tag {
    justify-self: end;
  }
}

/* ---------- 归档与巡检 ---------- */
.page-about .archive__grid {
  display: grid;
  gap: clamp(24px, 4vw, 56px);
}

.page-about .archive__copy p {
  margin: 16px 0 0;
  font-size: 15.5px;
  max-width: 40em;
}

.page-about .archive__list {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .archive__list li {
  display: flex;
  align-items: baseline;
  gap: 14px;
  font-size: 15px;
  line-height: 1.75;
  color: rgba(244, 240, 230, 0.78);
}

.page-about .archive__num {
  flex: 0 0 auto;
  min-width: 62px;
  font-family: var(--font-mono);
  font-size: 20px;
  letter-spacing: -0.02em;
  color: var(--cyan);
}

.page-about .archive__media {
  margin: 0;
}

@media (min-width: 900px) {
  .page-about .archive__grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    align-items: center;
  }
}

/* ---------- 覆盖与访问 ---------- */
.page-about .reach {
  padding: var(--about-pad) 0 0;
}

.page-about .reach__grid {
  display: grid;
  gap: clamp(24px, 3vw, 40px);
  margin-top: clamp(24px, 3vw, 40px);
}

.page-about .reach__stat {
  padding-top: 16px;
  border-top: 2px solid var(--ink);
}

.page-about .reach__val {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(44px, 7vw, 80px);
  line-height: 0.95;
  letter-spacing: -0.04em;
  color: var(--ink);
}

.page-about .reach__val small {
  margin-left: 10px;
  font-family: var(--font-mono);
  font-size: clamp(13px, 1.4vw, 17px);
  letter-spacing: 0.06em;
  color: var(--orange-deep);
}

.page-about .reach__txt {
  margin: 14px 0 0;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--slate);
  max-width: 34em;
}

.page-about .reach__note {
  margin: clamp(24px, 3vw, 36px) 0 0;
  padding-top: 18px;
  border-top: var(--about-line-soft);
  font-size: 15px;
  line-height: 1.85;
  color: var(--slate);
  max-width: 52em;
}

@media (min-width: 820px) {
  .page-about .reach__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

/* ---------- 下一步 ---------- */
.page-about .next {
  padding: clamp(40px, 6vw, 88px) 0 var(--about-pad);
}

.page-about .next__grid {
  display: grid;
  gap: 16px;
  margin-top: 24px;
}

.page-about .next__card {
  display: block;
  padding: clamp(20px, 3vw, 34px);
  border: 1px solid var(--hair);
  text-decoration: none;
  color: inherit;
  transition: transform 0.25s var(--ease), border-color 0.25s var(--ease),
    background-color 0.25s var(--ease);
}

.page-about .next__card:hover,
.page-about .next__card:focus-visible {
  transform: translateY(-3px);
  border-color: var(--cyan);
  background: rgba(169, 198, 201, 0.08);
}

.page-about .next__num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--orange-deep);
}

.page-about .next__card h3 {
  margin: 10px 0 0;
  font-size: clamp(20px, 2.2vw, 26px);
  line-height: 1.3;
}

.page-about .next__card p {
  margin: 10px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--slate);
}

.page-about .next__go {
  display: inline-block;
  margin-top: 16px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--orange-deep);
}

.page-about .next__foot {
  margin: 24px 0 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--slate);
  max-width: 48em;
}

.page-about .next__foot a {
  color: var(--orange-deep);
  text-decoration: none;
  border-bottom: 1px solid rgba(184, 56, 10, 0.4);
}

.page-about .next__foot a:hover {
  color: var(--ink);
  border-bottom-color: var(--ink);
}

@media (min-width: 820px) {
  .page-about .next__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

/* ---------- 桌面端左侧粘性刻度 ---------- */
@media (min-width: 900px) {
  .page-about .timeline {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    column-gap: var(--about-gap);
    align-items: start;
  }
  .page-about .timeline > .eyebrow {
    grid-column: 1 / -1;
  }
  .page-about .tl-rail {
    position: sticky;
    top: calc(var(--header-h) + 32px);
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding: 0;
    border-bottom: 0;
    border-left: 2px solid var(--hair-soft);
  }
  .page-about .tl-rail__link {
    padding: 10px 0 10px 18px;
    margin-left: -2px;
    border: 0;
    border-left: 2px solid transparent;
  }
  .page-about .tl-rail__link:hover,
  .page-about .tl-rail__link:focus-visible {
    border-left-color: var(--cyan);
    color: var(--ink);
  }
}

/* ---------- 图片与动效 ---------- */
.page-about .media-frame img {
  display: block;
  width: 100%;
  height: 100%;
  max-width: 100%;
  object-fit: cover;
}

@media (prefers-reduced-motion: reduce) {
  .page-about .next__card,
  .page-about .tl-rail__link {
    transition: none;
  }
  .page-about .next__card:hover,
  .page-about .next__card:focus-visible {
    transform: none;
  }
}
</main>